Hey, do you have any other advice? I've never ridden in the area, so I'm really looking forward to it, but worried about surprises of the bad kind.

I have done this ride 2 years ago. Dont worry about the suprises, They are what make the trip. The people we met out in the not much of the Navajo Nation were awesome. We did get the permit at the hotel for Peach Springs and the Ranger was great also. Get you beer BEFORE you head down to the river. Store just outside the rez to the west.
Torroweep is a must. You can get some strong feelings in that area. Plan on spending the night in the cave at the camp ground.